Research On Scanning Path Optimization Algorithm For Laser Selective Melting

In recent years,with the rapid development of additive manufacturing technology,metal additive manufacturing technology has begun to shine in the manufacturing field.As one of the most representative metal additive manufacturing technology,Selective Laser Melting(SLM)technology uses high-energy density laser beam to selectively melt metal powder layer by layer,and it is especially suitable for the complicated parts with high requirements on forming precision.It shows good technical foreground and application advantages in the field of aviation,aerospace and medical treatment.Laser scanning path planning as a key part of the SLM forming process is an effective process strategy for equalizing the temperature field of the forming part,avoiding stress concentration and preventing deformation cracking.Efficient,accurate and reasonable planning of the laser scanning path is of great significance for improving the processing efficiency of the process data,prolonging the life of the laser scanning system and improving the forming quality of the sample.In view of this,this article mainly focuses on the scanning path generation technology for the laser selective melting,and focuses on from three aspects:improving the efficiency of path planning,designing the path planning strategy and equalizing the temperature field of forming parts,the main research work is as follows:For the data preprocessing requirements of the scanning path generation algorithm,data storage structure of slicer contour based on contour tree and contour relation matrix is proposed.The rotation of the contour data by the inner and outer contour differentiation algorithm is indentified.Finally,the efficiency of these two data structures combined with experiments is analyzed and compared.Aiming at the problem of low filling efficiency of lattice structure,this paper proposes a parallel scan path generation algorithm based on single connected area.By analyzing the complexity of the algorithm and experimental results,it is verified that the proposed algorithm has better filling efficiency than the traditional parallel scan path generation algorithm.In order to balance the temperature field of forming parts and improve the forming quality,a quadrant-guided pseudo-random islanding scanning path generation strategy is proposed and designed.According to the contour of the slice,the partition direction is adaptively decided,plane coordinate quadrant is used to divide the forming area,partitioning of scan paths is selectively implemented based on quadrant order and random selection algorithm,by avoiding long-term scanning,the temperature field during the forming process can be effectively balanced.